Thursday, 19 January 2017

Buy Lego. Save the world.

A friend of mine who works at Surrey Satellite Technologies Limited alerted me to this pretty neat thing:  Lego has a scheme whereby proposed kits and designs can be produced by them if they receive enough support on a community website.  Someone has proposed a kit for the Galileo Global Navigation Satellites, parts of which are made here in Guildford.  If you'd like to see the kit made available, please add your support at the Lego Galileo Spacecraft page.  It doesn't oblige you to buy one when it gets to market, but Lego is pretty cool stuff, and Lego are also a place where at least I feel comfortable spending my money, given that every time we spend money we are undertaking an act about as political as anything else we do.


Friday, 13 January 2017

Applications of Nuclear Physics

A really nice and extensive article on many of the uses of nuclear physics appeared on the arXiv this week, written by Anna Hayes of Los Alamos Lab.  As well as including the most obvious applications (weapons and power) and perhaps the most widespread, as well as the first, application (medical), it also covers some of the neat uses in areas like geology, where the study of isotopic abundances in things such as groundwater can tell you what it going on far underground.  I've yet to read the whole thing yet, but it looks definitely worth bookmarking as a go-to piece whenever you are looking to discuss the range of things nuclear physics is applied to.

The figure attached to this post is from the paper, showing some of the ancient (pre-historic) natural nuclear fission reactors that existed in what is now Gabon, detected by the unusual isotope ratio of the remaining uranium, as well as some fission products.  See Anna's paper for more details!

Sunday, 18 December 2016

Hamish, dob 17/12/2016 <3

I'd like to present the results of a recent fusion-fission reaction.  One event was detected, on Saturday morning, with the final product observed to have a mass of 2.45 × 1030 MeV/c2. As a working name, we have have assigned Hamish, though obviously it needs to be ratified by the appropriate authority, via the Guildford Register Office.

The initial reaction products are remarkably more or less as they were before the reaction, though some evidence of decay seems to have taken place.  The results of previous successful experiments (codenamed Flora and Alba) are both delighted about this new emanation. 

Friday, 2 December 2016

More new isotopes

I posted not so very long ago about the announcement of the discovery of a hitherto unobserved isotope of lead.  The same laboratory has now had the announcement published about the observation of two further new isotopes; 240Es (Einsteinium, element number 99) and 236Bk (Berkelium, element number 97)

Congratulations to the team, drawn from the home institution of the laboratory, Jyväskylä University, as well as from collaborating institutions around the world.

If you want to read the research paper, it is published as an open access paper (i.e. anyone can read it without a subscription to the journal) here.  The publication date of the journal issue in which the paper features is in 2017, strangely.  


Thursday, 24 November 2016

The IBA prize for applied nuclear science

I noticed today in the electronic newsletter from the European Physical Society that the call for nominations for the IBA prize is mentioned there.  The prize is sponsored by the IBA company, whose business is in proton therapy, and it is awarded to one or several individuals for outstanding contributions to applied nuclear science including nuclear methods in medicine.  If any readers of this blog know of anyone that is deserving of the prize, please follow the link above to find the nomination form.  The deadline for nomination is 15th Jan 2017.

You can see a list of previous prizewinners here, and a picture of the last winner, Prof. Salehpour, accompanying this blog post.

Friday, 18 November 2016

"Do while" annoyances

Since I'm teaching a computing class this morning, here is a purely computer programming related post.  One of the students was having a problem with his code, using a do-while construct in the Fortran language.  This runs a block of code while a certain condition is true.  Here is a full example program which you can compile with e.g. the free gcc compiler:

PROGRAM dowhile

  IMPLICIT NONE
  INTEGER :: i, j

  i=1
  j=2
  DO WHILE (i<5)
     i=10
     j=20
  END DO
  WRITE(6,*) i, j

END PROGRAM dowhile


Now, the DO WHILE construct says that we run the code between the DO and END DO statements until the variable i is less than 5.  One may wonder, then, in the example, what value of j will be printed after exiting the loop.  If you know the rule that Fortran works by, then you know that the check of the condition i<5 takes place only each time the loop starts, and not continuously, so the line j=20 gets executed even though i<5 is no longer true at that point.  It is perhaps a little counter-intuitive, and can certainly lead to mistakes.  For that reason, I don't teach the DO WHILE construct in the year 1 computing course, but instead  "IF (i<5) exit", which can be inserted wherever in the loop the user wants the test to be done.  Enterprising students will, of course, find out about DO WHILE on the internet and make use of it. 

Thursday, 3 November 2016

New isotope of lead discovered

Yesterday, the journal Physical Review C published a paper announcing the observation of the isotope 178Pb – an isotope of lead with 96 neutrons and 82 protons.   This ratio of neutrons to protons is pretty extreme for such a heavy element, where the large positive charge of the 82 protons tend to prefer to be padded out with more neutrons than that.  126 neutrons is the number producing the most abundant isotope, so the one just discovered in a reaction at the laboratory at Jyväskylä University in Finland has an amazing 30 neutrons fewer than that most stable isotope.  At the other end of the scale, the heaviest lead isotope so far observed is 220Pb, with 138 neutrons.

The lead (no pun intended) author on the discovery paper is a PhD student, originally from Syria, who is studying at Jyväskylä.  Well done to all involved!